I found at least one thing that's changed, and for me it's an important one;

On my 2011 MBP I had a lot of trouble to install Lion preview 4, because there's a file in it that prevents the system from rebooting (so it stalls the install at the reboot that normally occurs halfway).
After installing it from another Mac (using the MBP in target mode) I had to manualy remove a file and replace it with a file of the same name from my 10.6 system.
The file is used for the wi-fi connection, and while I could now boot (with some strange stuff going on during boot, but still) and use Lion, there was one drawback: my MBP would not remember my wi-fi network.
I had to point it to my own network every time after rebooting.

After this update the network is being remembered like it should, and the boot sequence is 'cleaner'.
Me happy :-)

The hatched background used across OS X now (in both the original dark and new light forms) originally appeared as the background of folders in iOS 4, so I call it the folder background, because that's how many people know it.

Here's the dark form (like on the login screen):

And the new light form (behind the Spaces in Mission Control and as the default background in Safari, interestingly enough):

Apple has announced that it will be distributing Mac OS X Lion exclusively through the Mac App Store and not in retail packages using optical discs.

So, for those in an enterprise where everything goes through a purchasing group. How are we going to get users upgraded as they wish to without them signing into their itunes account and ordering one license at a time with their corporate card (which is against company policy) and then filling out expense reports?

Apple has announced that it will be distributing Mac OS X Lion exclusively through the Mac App Store and not in retail packages using optical discs.

So, for those in an enterprise where everything goes through a purchasing group. How are we going to get users upgraded as they wish to without them signing into their itunes account and ordering one license at a time with their corporate card (which is against company policy) and then filling out expense reports?

With the greatest of respect, your company's policy is nothing to do with Apple.

What Apple may do is release optical versions of the software for enterprise use after the initial release. There's no rush because we all know no good enterprise installs new software that soon. They wait until it's gone through the teething problems etc. Also, most large enterprises are monolithic and won't upgrade very quickly regardless of any other factors. They may also just see no real productivity benefit and not want to lay out that cash.

Is there anything stopping your company from setting up a company iTunes account and just buying it once? That's a genuine question, I'm not being difficult. At worst you could buy one version for every 5 employees or something. I've never read iTunes' T&Cs with enterprise in mind.

The hatched background used across OS X now (in both the original dark and new light forms) originally appeared as the background of folders in iOS 4, so I call it the folder background, because that's how many people know it.

With the greatest of respect, your company's policy is nothing to do with Apple.

What Apple may do is release optical versions of the software for enterprise use after the initial release. There's no rush because we all know no good enterprise installs new software that soon. They wait until it's gone through the teething problems etc. Also, most large enterprises are monolithic and won't upgrade very quickly regardless of any other factors. They may also just see no real productivity benefit and not want to lay out that cash.

Is there anything stopping your company from setting up a company iTunes account and just buying it once? That's a genuine question, I'm not being difficult. At worst you could buy one version for every 5 employees or something. I've never read iTunes' T&Cs with enterprise in mind.

No disrepect taken at all. This is nothing but an internal issue - Even though we are a huge company our OS X clients are unmanaged and unsupported. Not something that I and others have not tried to change several times. So, we will have users immediately asking for it and maybe just telling them no for now is the answer. Just trying to be proactive as much as our situation will allow.

Apple has announced that it will be distributing Mac OS X Lion exclusively through the Mac App Store and not in retail packages using optical discs.

So, for those in an enterprise where everything goes through a purchasing group. How are we going to get users upgraded as they wish to without them signing into their itunes account and ordering one license at a time with their corporate card (which is against company policy) and then filling out expense reports?

Lion supports net install. Your IT department needs to get a copy of Lion, then they can remotely install it to every machine on the network.